tl;dr black powder and gunpowder must be under pressure to properly deflagrate, and they’re unassuming

@NPR:

They are cheap, easy to build and inconspicuous. And as the explosions this week at the Boston Marathon show, pressure cooker bombs can be devastatingly effective weapons.

But why would someone place a bomb inside a common kitchen implement? As we explained two years ago in an article about the increased use of pressure cookers (for cooking, not bombs):

“It works using basic principles of science: Water normally boils at 212 degrees Fahrenheit — and doesn’t get hotter. But under pressure, it boils at about 242 F and stays there. Raising the boiling point lets the food cook at the higher temperature, which cuts cooking time by two-thirds or more.”

The same principle that increases the boiling point inside a pressure cooker also can be used to amplify the force of an explosive.

As NPR science reporter Geoffrey Brumfiel notes, “If you seal a pressure cooker, the steam builds up in the vessel. It helps to raise the temperature and cook food, but sometimes when the cooker fails, you get a very energetic release.”

“Forced marches” or “humps” are a regular part of military training, brisk walking over tough terrain while carrying gear that could help a soldier survive if stranded alone. These soldiers, participating in “Tough Ruck 2013,” were doing the 26 miles of the Boston Marathon to honor comrades killed in Iraq and Afghanistan, or lost to suicide and PTSD-related accidents after coming home.

When the explosion went off, Fiola and his group immediately went into tactical mode. “I did a count and told the younger soldiers to stay put,” Fiola says. “Myself and two other soldiers, my top two guys in my normal unit, crossed the street about 100 yards to the metal scaffoldings holding up the row of flags. We just absolutely annihilated the fence and pulled it back so we could see the victims underneath. The doctors and nurses from the medical tent were on the scene in under a minute. We were pulling burning debris off of people so that the medical personnel could get to them and begin triage.”

Once the victims were transported away for further medical care, Fiola and the others stood guard around the blast area. “We switched to keeping the scene safe, quarantining the area and preventing people from entering. There was a guy behind me covered, just covered, in his own blood, and I started to smell some smoke. I turn around to look and he’s actually on fire, from a piece of whatever caused the explosion. I saw the smoke coming from his pocket so I reached in and pulled it out. It was his handkerchief, on fire.”

Time will tell whether the gold bugs or the skeptics are right, but what’s being overlooked is that it doesn’t matter whether Bitcoin makes it as a store of value or a unit of account for it to work as a medium of exchange. Even if the Bitcoin market remains volatile and never pans out as a good store of value or unit of account, one can imagine users converting their dollars or euros to bitcoins for just long enough to make a transaction; perhaps just minutes. And as long as it works as a medium of exchange, it is the true digital cash that was missing from the cypherpunks’ predictions.

With a little bit of effort, today you can purchase bitcoins anonymously with physical cash. You could then do all sorts of things the government doesn’t want you to do. You could buy illegal drugs on the notorious Silk Road, an encrypted website that has been operating with impunity for the past two years facilitating annual sales estimated at almost $15 million. You could gamble at various casinos or prediction markets, buy contraband Cuban cigars, or even give money to WikiLeaks. Dissidents in Iran or China can use Bitcoin to buy premium blogging services from WordPress, which now accepts payment in the currency. Perhaps more importantly, Bitcoin makes the cypherpunks predictions of markets for stolen secret information and even assassinations feasible.

Last month, the Treasury Department issued guidance on how it plans to regulate Bitcoin exchanges. This is good news for the currency since it implies the government is looking to regulate its use rather than prohibit it. Confronted with Bitcoin’s potential, it’s not reasonable to expect that Treasury’s money laundering cops would simply let it be. So it’s a sensible approach for them to take because Bitcoin, much like BitTorrent, can be used for both licit and illicit purposes and would in any event be difficult to shut down.

Prior to the fictional events in “Breaking Bad” ricin was used several times as both a tool of assassination as well as a weapon of terrorism. It’s cheap and easy to make and no known antitoxins existed until just a couple of years ago.

The beans themselves can kill an adult if injested, and the amount of pure ricin extract that’s lethal is less than the amount of venom a bee stings you with.

James Goodale has a message for journalists: Wake up. In his new book, Fighting for the Press (CUNY Journalism Press, 2013), Goodale, chief counsel to The New York Times when its editors published the Pentagon Papers in 1971, argues that President Obama is worse for press freedom than former President Richard Nixon was.

The Obama administration has prosecuted more alleged leakers of national security information under the 1917 Espionage Act than all previous administrations combined, a course critics say is overly aggressive. Former New York Times executive editor Bill Keller wrote in a March op-ed that the administration “has a particular, chilling intolerance” for those who leak. If the Obama administration indicts WikiLeaks founder Julian Assange for conspiracy to violate the Espionage Act, Goodale argues, the president will have succeeded where Nixon failed by using the act to “end-run” the First Amendment.

Goodale spoke with CJR about why he chose to write about the Pentagon Papers now and what he sees as the key threats to press freedom today. The conversation has been condensed and edited for length and clarity. Fighting for the Press comes out on April 30.

Bruce Schneier’s a security specialist with his own Internet meme. And while most people believe that technology elevates, improves things, Schneier holds that technology magnifies, makes things bigger, good and…